LONDON, England (CNN) -- British Airways posted the airline's worst annual loss since its privatization in 1987 as its chief executive declared there were "absolutely no signs of recovery" in the industry.

BA CEO Willie Walsh says he's never seen conditions in the airline industry so bleak.

The airline slumped from profit to loss in the last financial year.

During the year ended March 31, its operating loss swelled to £220 million ($348 million) from a restated profit of £878 million ($1.4 billion) in 2008.

"I'm 30 years in this business and I've never seen anything like this. This is by far the biggest crisis the industry has ever faced," BA chief executive Willie Walsh told CNN's Richard Quest. Follow Quest on Twitter

Demand for the airline's passenger seats and cargo holds fell during the last financial year, while its fuel bill rocketed to almost £3 billion ($4.7 billion).

"None whatsoever, and that's across the board," he said. "In all of the markets we're operating in we see no evidence of recovery at this stage. I think there's some evidence of it bottoming out in some markets but absolutely no signs of recovery at this point."

Like its premium-class competitors, British Airways is losing customers to cheaper rivals.

BA's premium passenger numbers fell 13 percent in the second half of last year, in line with the industry average.

Total traffic fell 3.4 percent and while BA carried 33.1 million passengers in last year, a drop of 4.3 percent on the previous year.

The dip in demand for British Airways flights has forced a switch in strategy at the premium airline from yields to volume.